This invention deals with improvements in intermodal rail vehicles of the type shown in U.S. Pat. Nos. 5,291,835, 5,890,433 and 6,050,197.
The above-identified prior art discloses novel intermodal vehicles for use in forming a train of highway trailers including leading and trailing trailers which are interconnected to each other and supported by the intermodal vehicles. The intermodal vehicle of this invention, as well as the prior art referred to above, is intended for use with highway trailers of all configurations, including trailers especially designed to haul so-called xe2x80x9cISOxe2x80x9d shipping containers. Each of the highway trailers include a leading coupler socket assembly at the leading end and a trailing coupler socket assembly at the trailing end, each of the socket assemblies being provided with a pair of vertically spaced apart aligned apertures for receiving a coupling pin. The intermodal vehicle is characterized by a lower frame assembly supported by two rail wheel assemblies, and a unitary upper lifting frame assembly supported on the lower frame assembly by spring means. The spring means include air springs which are so arranged that when air is removed from the air springs, the upper lifting frame assembly will descend towards the lower frame assembly, and when air is introduced into the air springs, the upper lifting frame assembly will rise, at the same time raising any highway trailers which may be resting on the upper lifting frame assembly. To this end, the upper lifting frame assembly includes leading and trailing upwardly presented load carrying structures, each of the load carrying structures having an upper trailer support surface for engaging the bottom of a trailer. In addition, a coupler tongue is associated with each of the load carrying structures, the coupler tongue being adapted to be received in the coupler socket assemblies. Each tongue is provided with an aperture for receiving a vertically oriented coupling pin which is carried by each of the load carrying structures. The coupling pin is moveable vertically from a position below the trailer support surface to a position where it passes through the apertured socket assemblies for securing a tongue within the apertured socket assembly. U.S. Pat. No. 5,890,433 discloses that the upper frame assembly may be in two sections, each independently moveable, whereas U.S. Pat. No. 5,291,835 discloses only a single upper frame. In the prior art each tongue is supported for limited pivotal, rolling and pitching movement. It is also a feature of the above-referenced designs that the lower frame assembly is steerable with respect to the upper frame assembly. In the above-referenced designs, the load carrying structures are shiftable transversely, that is to say, from side to side perpendicular to the longitudinal centerline of the intermodal vehicle to facilitate the alignment of the trailer as it is connected to the intermodal vehicle. Additional features of the intermodal vehicle are disclosed in the foregoing patents. The prior art also discloses a novel transition vehicle which may be used to connect an intermodal vehicle to a conventional rail coupler.
The designs shown in the foregoing patent literature have validated the concept of making up a train with highway trailers supported on intermodal vehicles, each of the highway trailers being provided with leading and trailing coupler sockets, which sockets can be secured to an intermodal vehicle by a coupler pin which extends through aligned apertures in the sockets, and through an aperture in a coupler tongue carried by the intermodal vehicle. However, these designs have been complex and a more simplified design is desired which obtains the basic benefits of the prior art.
It is an object of the present invention to provide a refined intermodal vehicle wherein the upper load supporting frame is a unitary welded assembly which is supported a pair of lower steerable lower frame assemblies, there being coupler tongues in the form of a single double ended drawbar carried by the upper frame assembly in fixed relationship to front and rear load carrying surfaces on the upper frame assembly, the drawbar having front and rear vertically extending apertures which received vertically movable coupler pins for securing the intermodal vehicle to front and rear highway trailers.
In the prior art designs referred to above special forms of air spring assemblies were required. However, such air springs are difficult to assemble and maintain. Therefore it is an object of this invention to use conventional air spring assemblies which overcome the inherent disadvantages of the prior art air springs of special design.
In U.S. Pat. No. 5,890,433 a steering mechanism is shown (at 72 in FIG. 5). In addition, steering dampers are provided (at 96 in FIG. 3) to restrain horizontal movement of the upper frame assembly relative to the lower frame assembly. In U.S. Pat. No. 6,050,197 the steering means is shown at 61 in FIG. 4D. In addition, steering dampers are connected with the top of each associated single convolution air spring. It is an object of the present invention to provide an improved steering mechanism which does not require separate dampers. Thus, a novel steering mechanism is provided which consists of vertically extending cylindrical guide rods, each of which is received in apertured plates, each of the plates being mounted for spring resisted movement.
U.S. Pat. No. 6,050,197 teaches the desirability of a loading ramp. However, the loading ramp of the prior art design does not center the trailer onto the intermodal vehicle. Therefore, it is an object of the present invention to provide an improved loading and centering ramp. This design feature acts to both ramp the trailer up onto the intermodal vehicle and to shift it from side to side as it is being ramped up so that it is centered within a fraction of an inch over the coupler pin, the final centering being accomplished by a tapered coupler pin. This design eliminates the need for the load carrying surface to be transversely shiftable.
In the prior designs referred to above, while stop bars are provided, no mechanism is provided to cushion the stop bars. It is an object of the present invention to provide a stop bar mechanism which limits the relative motion of a highway trailer to the intermodal vehicle during train makeup, wherein the stop bar is provided with a cushioning mechanism.
It is a further object of the present invention to provide a new and novel mechanism for insuring that the upper frame assembly is maintained in its raised position even if there is a failure of air pressure. To this end a back up suspension system, in the form of coil springs, is provided. The coil springs are received in recesses in the upper frame assembly when the upper frame assembly is fully lowered relative to the lower frame assembly. However when the upper frame assembly is raised, the coil springs are prevented from entering into the recesses by shiftable plates in the form of paddles which cover the openings to the recesses. When the train of highway trailers is moving over the rails the coil springs serve to act as a backup suspension system. However, in the event of failure of the air springs, the coils springs will prevent the upper frame assembly from lowering when it is desired to maintain the upper frame assembly in a raised position.
It is a still further object of the present invention to provide an improved coupler pin and coupler pin operating mechanism which will permit the coupler pin to rock with the trailer when in its lifted coupling position, even though the drawbar may not be rocking.
It is yet another object of the present invention to provide a new and improved transition vehicle for coupling a train of highway trailers to conventional rail vehicles.
The foregoing design features will be better understood after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which the best mode of practicing this invention is illustrated.